/Engine/Source/Runtime/Core/Public/Misc/MapErrors.h
Map should have KillZ set.: This warning is caused when the map's KillZ in the WorldInfo properties is set to the default value. All maps should specify a KillZ appropriate for the level so that players cannot simply fall forever until they reach the playable world bounds.
static [FLazyName](API\Runtime\Core\UObject\FLazyName) NoKillZ;